This invention relates to a pressure regulator for keeping a predetermined medium pressure at a preferred, constant value, said medium pressure being controlled in dependence on a constant weight load.
In keeping a predetermined medium pressure or secondary pressure at a constant value, pressure regulators up to now usually have been used in which a spring force provides for keeping the pressure of the output flow at a constant value. Pressure regulators using this known technique have proved to have certain drawbacks. At step changes in a input medium or primary pressure of the regulator a constant pressure of the secondary flow has not been obtained owing to the proportionality of the spring but said pressure has increased or decreased depending on how the pressure of the supplied medium has varied. At different outputs of secondary flow, it has also been proved that the pressure of the latter has varied dependent on how large the output has been.